TA7642 AM Radio Parts List

The TA7642 AM Radio requires the following widely available low-cost parts. I hope that the cost of the circuit will be within the range of the little whippersnapper's pocket money.

If you have built The Little Whippersnapper's Crystal Radio, and followed on to make Project Ultra, and then The Great Escape, Project Tom, is going to be very easy, as you just have to add some more components.

Hardware

• No. 6 Brass Screws ½-inch, quantity 24 from eBay
• No. 6 Brass Cups, quantity 24 from eBay
• Baseboard must be smooth softwood ½-inch thick, 4-inch wide and 12-inch long.

TA7642 Equivalent

• ZN414Z, or MK414, or CD7642, or UTC7642, or LMF501

Amplifier Chip

• LM386N

Resistors

• R1: 100 kΩ
• Rp:150 kΩ
• R2: 10 Ω
• VR: 10 kΩ, Potentiometer Logarithmic, Maplin Code: JM77J

Electrolytic Capacitors

• Cp: 470 µF
• Cg: 10 µF
• C3: 1 µF
• C5: 220 µF

Non-Polarised Capacitors

• C1: 0.01 µF
• C2: 0.15 µF
• C4: 0.047 µF

Main Parts

• 365 pF Variable Tuning Capacitor
• Crystal earpiece
• Ferrite Rod 3/8-inch diameter, 3-inch or longer
• 36 s.w.g enamelled copper wire / Radio coil wire
• Connecting copper wire

Tools

• Pointed nose pliers
• Screwdriver
• Gimlet / Bradawl for the guide holes
• Wire Cutter or Stripper
• Sandpaper for cleaning terminals
• Cutter pliers
• Dad / Mum / Adult Supervision

Modern Tools & Materials

• Glue Gun - Marksman
• Antex Vintage Soldering Iron SK1 Kit
• Solder

Misc

• 3-inch diameter Loudspeaker, 8 Ω
• Potentiometer Mounting Bracket
• PP3 Battery clip
• PP3 Battery

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